Sequella will explore use of early-onset Ab produced by infection of rhesus monkeys with M. tb as a potential diagnostic for identifying or confirming absence of this disease in quarantined animals and nonhuman primate colonies. The current skin test reagent produces unacceptably high numbers of false negative and positive reactions. The purpose of this Phase I proposal is (a) to identify antigens of M. tb to which nonhuman primates (as opposed to humans) develop immunological reactivity, and (b) to determine the time course and immunoglobulin class of Ab produced to TB antigens in serum and in feces. The results of these studies will help select both the correct antigen(s) to detect early Ab and the type of Ab detection system (by Ab class) that will most appropriately form the basis of a new serologic or scatologic diagnostic. A successful Phase I study would stimulate a Phase II application to confirm Ab to the same or different antigens in M. bovis- infected rhesus monkeys, extend these observations to other nonhuman primates infected with the two etiologic agents of TB, identify the appropriate test format for highest sensitivity and specificity, and perform clinical trials to validate the serologic/scatologic diagnostic and compare it to the current skin test. PROPOSED COMMERCIAL APPLICATION: Sequella will develop a proprietary position with Mycos, Inc. on antigens that are specifically useful for the diagnosis of TB in nonhuman primates; Sequella will also patent any innovative technology it develops to detect Ab, (specifically anti-mycobacterial Ab) in serum or feces. Should a sensitive and specific diagnostic be the result of these studies, and the clinical evaluation suggests that this test is superior to the currently approved skin test, Sequella and its partners will seek approval of the diagnostic by the USDA as an adjunct or replacement for the skin test. With approval, Sequella and its partners will have such the diagnostic manufactured and marketed to interested veterinary groups, in private or public institutions.